This application is based upon and claims the benefit of priority from the prior Japanese Patent Application PH2001-055846, filed on Feb. 28, 2001; the entire contents of which are incorporated herein by reference.
The present invention relates to a route guidance apparatus and a method for executing route guidance for a pedestrian by presenting a route guidance sentence or a simplified map.
Recently, a route guidance apparatus for presenting a route guidance sentence and a simplified map to a destination for a pedestrian is developed. This route guidance apparatus is a simple portable device or is loaded to a portable communication terminal such as a cellular-phone or a personal data assistant (PDA).
A route guidance technique using the route guidance sentence and the simplified map is disclosed in the following two references.
(1) TECHNICAL REPORT OF IEICE, PRU95-215 (1996-02), xe2x80x9cInteractive Generation of a Route and Its Application to Generating a Sketch Map Drawing in a Map Image Information Systemxe2x80x9d Masahiko HORIE, Toshihiro KIMURA, Noboru BABAGUCHI, Seiichiro DAN and Tadahiro KITAHASHI.
(2) TECHNICAL REPORT OF IEICE, PRMU96-156 (1997-01), xe2x80x9cModeling of Geographic Road Structure for Generation of Sketch Map Image and Linguistic Guidexe2x80x9d Toshihiro KIMURA, Yoshihiro SUZUKI, Seiichiro DAN, Noboru BABAGUCHI and Tadahiro KITAHASHI.
As for generation of the route guidance sentence, in reference (1), for example, a sentence xe2x80x9cPlease go forward to the west direction by 20 meters.xe2x80x9d and xe2x80x9cPlease turn to the right at the junction.xe2x80x9d can be presented. However, especially, numerical value representing distance such as xe2x80x9c** metersxe2x80x9d is difficult for a pedestrian to apply. Furthermore, innumerable junctions exist in a town area, and the pedestrian often mistakes a junction indicated by the route guidance sentence for another junction. Accordingly, such route guidance sentence is not always easy for the pedestrian to sufficiently understand. In reference (2), for example, a route guidance sentence such as xe2x80x9cThis road joins another road.xe2x80x9d or xe2x80x9cYou advance to ** at a crossroads.xe2x80x9d is only presented. This route guidance sentence is more difficult for the pedestrian to understand than the route guidance sentence disclosed in the reference (1).
As mentioned-above, in the known route guidance technique, presentation of the route guidance sentence is not always easy for the pedestrian to understand, and it is often possible for the pedestrian to misunderstand a junction point, a joint point, or a divergence point indicated by the route guidance sentence.
It is an object of the present invention to provide a route guidance apparatus and a method to present route guidance easy for the pedestrian to understand.
According to the present invention, there is provided a pedestrian route guidance apparatus, comprising: a database configured to store map data including road network data and landmark data; a route search unit configured to search for a route from a departure point to a destination point from the road network data stored in said database; a road pattern analysis unit configured to analyze a road pattern of the route by referring to the road network data, and to obtain road pattern data as the analysis result; a route guidance information generation unit configured to generate route guidance information of the route using the road pattern data and the landmark data along the route; and a presentation unit configured to present the route guidance information.
Further in accordance with the present invention, there is also provided a pedestrian route guidance method, comprising: storing map data including road network data and landmark data in a database; searching for a route from a departure point to a destination point from the road network data stored in the database; analyzing a road pattern of the route by referring to the road network data; obtaining road pattern data as the analysis result; generating route guidance information of the route using the road pattern data and the landmark data along the route; and presenting the route guidance information.
Further in accordance with the present invention, there is also provided a computer program product, comprising: a computer readable program code embodied in said product for causing a computer to execute pedestrian route guidance, said computer readable program code having: a first program code to store map data including road network data and landmark data in a database; a second program code to search for a route from a departure point to a destination point from the road network data stored in the database; a third program code to analyze a road pattern of the route by referring to the road network data; a fourth program code to obtain road pattern data as the analysis result; a fifth program code to generate route guidance information of the route using the road pattern data and the landmark data along the route; and a sixth program code to present the route guidance information.